Difference Between 304 and 316 Stainless Steel
The main difference between 304 vs 316 stainless steel is the content of Chromium (Cr), Nickel (Ni) and Molybdenum (Mo). 304 stainless steel doesn’t contain Molybdenum while SS316 contains 2-3% molybdenum. In addition, AISI 304 has a 18% Chromium and 8% Nickel content while AISI 316 has a 16% Chromium and 10% Nickel.
304 vs 316 Stainless Steel in Chemical Composition
The following table shows the difference between 304 and 316 stainless steel in composition.
|SS304 vs SS316 Composition (%)|
|Steel Grade||C, ≤||Si ≤||Mn ≤||P ≤||S ≤||Cr||Ni||Mo|
SS304 vs SS316 in Mechanical Properties
304 vs 316 stainless steel properties
|SS304 vs SS316 Mechanical Properties|
|UNS||AISI||Tensile Strength (MPa) ≥||Yield Strength ≥ (MPa) at 0.2% Offset||Elongation (%, ≥, 50mm)||Brinell Hardness (HBW) ≤||Rockwell Hardness (HRBW) ≤|
SS 304 Stainless Steel
SS 304 is a versatile stainless steel and the most commonly used stainless steel, it is widely used to produce equipment and parts that require good corrosion resistance and formability, such as food equipment, general chemical equipment.
SS304 has excellent hot and cold processing and forming properties, can be processed to produce various products such as plates, pipes, wires, belts, strip, and tapes. It is suitable for manufacturing cold heading, deep drawing, and deep drawing forming parts. 304 stainless steel welding performance is good, can be welded using the usual welding method, no heat treatment required before welding.
SS 316 Stainless Steel
Because SS316 contains molybdenum (Mo), the resistance to pitting corrosion in the marine and chemical industry environment is much better than 304 stainless steel.
Variants of 316 stainless steel include low-carbon stainless steel 316L, nitrogen (N) containing high strength stainless steel 316N, high sulfur containing free cutting stainless steel 316F, and titanium containing improving intergranular corrosion 316Ti.
However, 304 and 316 steel also has shortcoming in terms of welding: After welding large steel parts, it may be easily cracked or subjected to intergranular corrosion. Therefore, post-weld annealing is required for stress relieving. To avoid this, it is recommended to use ultra low carbon 304L, 316L or stabilized stainless steel (321, 347 and 348), etc.